Marine power plant



Jan. 16, 1934. w B FLANDERS 1,943,860

MARINE POWER PLANT Filed Sept. 12, 1928 1'0 Source 0/ A fluid Erasure f36 ASYERN 45 AHEAD ASTERN SE(TION SECTION 89 TU INE INVENTOR 'IZW-B-Flunders C1, 6 WWW 4e F'LQ.Z. v ATTORNEY Patented Jan. 16, 1934UNITED STATES PATENT OFFICE MARINE POWER PLANT Application September 12,1928 Serial No. 305,504

6 Claims. (Cl. 60-21) My invention relates to a marine propulsionarrangement, and it has for its object to provide a reciprocating engineand a low-pressure turbine disposed in compound relation in order tosecure efficient utilization of energy of steam and rapid reversal.

In view of the fact that steam turbines are practically capable ofexpanding steam to lower absolute pressures than reciprocating engines,it 1 has been recognized that low-pressure turbines might be usedadvantageously with reciprocating engines. Such an arrangement, however,is subject to operating difficulties in marine service. While thelow-pressure turbine may have ahead and astern sections capable ofalternate connection to the reciprocating engine, dependent upon whetherit is desired to operate ahead or astern, nevertheless, when changingover from ahead to astern operation, or vice versa, the passage of steamfrom the reciprocating engine may be greatly diminished or entirelyinterrupted for a certain length of time. This, together with theinertia of moving parts of the turbine apparatus, makes reversalsomewhat difiicult and slow.

In accordance with my invention, I provide means for supplyinghigh-pressure steam to the turbine sections, such means being under thecontrol of the reversing mechanism of the reciprocating engine, whereby,when the reversing mechanism is operated, high-pressure steam isadmitted to the proper turbine section. In this way, immediate admissionof high-pressure steam to a turbine section serves to overcome theinertia of the rotor and connected parts and to secure reversal thereofvery quickly.

Apparatus made in accordance with my invention is illustrated in theaccompanying drawing, forming a part of this application, in which:

Fig. 1 is a diagrammatic View of my improved power plant;

Fig. 2 is a diagrammatic view showing a modified arrangement, havingautomatic control mechanism for admitting high pressure steam duringreversing operation and for shutting off the same when the reversingoperation is completed; and

Fig. 3 shows a detail of the control mechanism of Fig. 2 in differentposition.

r Referring now to the drawing more in detail, I

0 show a multiple expansion reciprocating engine,

at 10, driving a propeller shaft 11, having a propeller 12 connectedthereto. High pressure steam from any suitable source, such as boilers(not shown) is supplied through the conduit '7. A conduit 8, connectingtherewith, passes the steam to the inlet of the reciprocating engine,and interposed in the conduit 8 is a throttle valve 9 for controllingthe supply of steam to the reciproeating engine.

Steam exhausted from the engine 10 is supplied by a suitable line 13 toa low pressure turbine 14. After energy is abstracted from the steam bythe turbine 14, the exhaust passes to the condenser 15. The rotor of theturbine is connected to the shaft 16, the latter entering the casing 17of a suitable reduction gear and being connected to a pinion 18 meshingwith the gear 19 carried by the shaft 11. The turbine 14 includes anahead section 20 and an astern section 21 so that the turbine is capableof operation in either direction to secure ahead and astern propulsion.

The exhaust line 13 from the reciprocating engine is connected tobranches 23 and 24 leading, respectively, to the ahead and asternturbine sections 20 and 21. A high-pressure steam line 25, communicatingwith the conduit '7, is provided with branches 26 and 27 leading,respectively, to the forward and astern sections 20 and 21. Valves 28,29, 30 and 31 are arranged so in the branches 23, 24, 26, and 27,respectively, and such valves are connected to mechanism at 32, which isoperated by the engine reversing lever 34. The latter also operates thereversing mechanism 33 of the reciprocating engine. On the drawing, thereversing mechanism 33 has been moved from its correct position withrelation to the reciprocating engine in order to show its operativerelation to the mechanism 32.

While the interconnecting mechanism may take any suitable form, I show,,by way of example, reversing mechanism including a lever 34, which isconnected to a link 35, the latter being pivoted to a lever 36 and thelever being connected to a link 3'7. The link 37 is connected tosuitable crank arms carried by the valves. A valve 38 is provided in thehigh-pressure steam line 25 and it is positioned conveniently to thereversing mechanism 33 for a purpose to be hereinafter explained.

The operation of the apparatus described is as follows: Assuming thatthe reciprocating engine, at 10, and the turbine, at 14, are inoperation and it is desired to reverse them, the reversing mechanism 33is operated and this, through the linkage 32 serves to open one of thevalves 30 and 31 and to close the other, thereby admitting high pressuresteam to the turbine to reverse its direction. During the period ofreversing of the reciprocating engine the flow of steam therethrough islimited by the speed at which the pistons move. Also, the rotor of theturbine has considerable inertia in the direction of its rotation priorto reversal. Hence, the prompt admission of high pressure steam to theproper turbine section serves to overcome rapidly the inertia of theturbine and to reverse it quickly.

The valves 28 and 30 are arranged to open and to close together and thesame is true of the valves 29 and 31. When the reversing mechanism 33 isoperated, one pair of valves is opened while the other is closed. Hence,with the admission of high pressure steam to a turbine section, thecorresponding valve controlling the admission of exhaust steam to thesame section is opened, the high-pressure steam coming into actionpromptly as above pointed out. After reversal has been eifected andthere is normal flow of exhaust steam in the line 13, the supply ofhigh-pressure steam may be shut off by closing the valve 38. If this isdone, the valve should be again opened before reversing.

In Fig. 2, I show a modification of my inven tion, wherein areciprocating engine 10 and a turbine 14 are geared for driving apropeller 12, as in the first embodiment. In this embodiment however,automatic or governor controlled means are provided for admitting livesteam to the turbine for reversing the direction of rotation, and forautomatically shutting elf the sup ply of live or high-pressure steamwhen the turbine has attained a predetermined speed in the desireddirection. Such parts of this embodiment as are also found in the firstembodiment are designated by the same reference numeral.

Exhaust steam from the reciprocating engine is passed to the aheadsection of the turbine, during ahead operation, through the conduit 13and a branch conduit 23a. In this case, exhaust steam is not used in theastern section 21, and, therefore, a branch conduit 24a leads from theconduit 13 to the condenser 15. A two way valve 41 is provided at theconnection between the branches 23a and 24:]. with the conduit 13, andis adapted to place the conduit 13 in communication with either of saidbranch conduits. two way valve 41 has a crank arm 42 for operationthereof, the latter being connected with the reversing mechanism 33through a rod 91, a bell crank lever 92, and a rod 8'7.

To obtain a governing fluid pressure which will control the admission ofhigh-pressure steam to the turbine 14 until the turbine has attained thedesired speed in the desired direction, a. gear pump 43 is provided,said pump being driven by the turbine 14 in any suitable manner, at aspeed proportional to the speed of the turbine, and in a directiondetermined by the direction of rotation of the turbine shaft. In theconstruction shown on the drawing, the gear pump is connected with theturbine shaft 16 through a beveled gearing 43'. The gear pump is soarranged that when the turbine is rotating in ahead direction, fluidunder pressure is transmitted to a conduit 44, and when the turbine isoperating in astern direction, the pump passes fluid under pressure to aconduit 45. A reservoir 46 contains a body of any suitable lieuid,preferably lubricating oil, and a conduit 4'7 communicates with thebottom thereof. The conduit 4'7 communicates with the conduits 44 and45, at points near the gear pump 43, through the branch conduits 48 andrespectively. Check valves 51 and 52 are provided in the branches 48 and49, respectively, thereby permitting the gear pump to draw liquid fromthe reservoir 46, but preventing the loss of fluid pressure thereto.

A conduit 53, communicating with the conduit 44, has a restrictedorifice 54 therein, and a conduit 55, communicating with the conduit 45,has a restricted orifice 56 therein. The conduit 53 communicates withthe conduit 55 beyond the orifices, and the conduit 55 communicates withthe reservoir 46. The orifices 54 and 56 permit the escape of excessliquid to the reservoir 46, imposing a pressure on the liquid, how ever,which is a function of the speed of the gear pump 43. It will thus beseen that when the turbine 15 is operating in ahead direction, the gearpump 43 provides a fluid pressure in the conduit 44 which is a functionof its speed, and when the turbine is operating in astern direction, thegear pump provides a fluid pressure in the conduit 45 which is afunction of its speed.

The supply of high-pressure steam to the ahead sec ion in thisembodiment is controlled by a valve 61 interposed in the conduit 26, andthe supply of high-pressure steam to the astern section is controlled bya valve 62 interposed in the conduit 2'7. The valve 61 is actuated by apiston 63 operating in a cylinder 64. A spring 65 biases the piston 63to open the valve 61.

The valve 62 is operated by a similar piston 66 operating in a cylinder67 and also biased to open lie valve by a spring 68. A conduit 69communicates with the cylinder 64 for supplying actuating fluid thereto,and a conduit '71 communicates with the cylinder 6'7 for the samepurpose.

The supply of fluid pressure from the conduits 44 and 45 to cylinders 64and 67 for operating the valves 61 and 62, is controlled by a pilotvalve '72, which, in turn, is actuated by the re versing mechanism 33 ofthe reciprocating engine 10 through the rod 8'7, a bell crank lever 88,and a rod 89. The pilot valve '72 has piston portions '73, '74, '75 and'75, and operates in a cylindrical valve casing '77. The pilot Valve '32is shown in Fig. 2 in the position corresponding to neutral position ofthe reversing mechanism 33.

The conduits '71 and 69 communicate with the casing '77 at pointsintermediate the piston portions '74 and '35. but adjacent to thesepiston portions, respectively. The conduits 45 and 44 communicate withthe valve casing '77 at points which are always in communication withthe space between the piston portions '73 and '74 and between the pistonportions '75 and '76, respectively. A conduit '78, which furnishes fromany suitable source liquid pressure of a value sufficient to close eachof the valves 61 and 62. communicates with the casing '77 at a centralpoint, and is always in communication with the space between the pistonportions '74 and '15.

A throttle valve 81 is preferably interposed in the cond it 25 betweenthe conduit '7 and the branch conduits 26 and 2'7. This valve is actuated by a piston 82 operating in a cylinder 83. The piston 82 isbiased in a direction to close the valve 81 by a spring and the conduit753 communicates at the lower end of the'cylinder 83, admitting fluidpressure thereto in a direction to open the valve against the force ofthe spring 84. A stem 85 is screw-threaded through the upper end of thecylinder 83 and is adapted to operate the piston 82 against the fluidpressure by means of a handwheel 86 attached thereto.

The operation of this embodiment of my in vention is as follows:

Assume the apparatus is to be in ahead operation.. The throttle valve 9is open and the reversing mechanism 33 is in ahead position in which therod 8'7 is at the right-hand end of its travel. The rods 91 and 89 areat the upper ends of their travel, the former maintaining the valve 41in position to close communication with the branch conduit 24c and topermit the exhaust steam from the engine 16 to pass to the ahead sectionof the turbine.

The rod 89 holds the pilot valve '72 in its upper position, as shown inFig. 3. The conduit 69 is in communication with the conduit 44, andiluid pressure from the gear pump 43 is, therefore, imposed on thepiston 63 to close the valve 61. The conduit 71 is in communicationwith. the conduit '78 which provides fluid pressure to close the valve62.

In normal ahead operation, therefore, only exhaust steam from thereciprocating engine is admitted to the turbine and, therefore, the mosteconmical operation of the apparatus is obtained.

Suppose now that it is desired to reverse the direction of operation.The throttle valve 9 is closed to shut off the supply of steam to thereciprocating engine. The reversing mechanism 33 is actuated by means ofthe lever 34 to astern position, the rod 87 being moved to the left andthe rods 91 and 89 being moved to lowermost position. The throttle valve9 is again opened. The valve 41 closes communication with the aheadsection and the exhaust steam from the engine is passed to the condenser15 through the branch conduit 24a.

The pilot valve 72 is also moved to lowermost position by the rod 89,the piston portion 74 being disposed between the ports communicatingwith the conduits '71 and '78. The conduits 78 and 69 communicatethrough the space be tween the piston portions 74 and l5, and fluidpressure from the conduit 78 is, therefore, communicated to the piston63 to retain the valve 61 in closed position.

The conduit 71, however, is placed in communication with the conduit 45,through the space between the piston portions 73 and J4, and as theturbine is operating in ahead direction, there is no pressure in thelatter conduit. The spring 68, therefore, moves the piston 66 to openthe valve 62, and high-pressure steam is admitted to the astern sectionof the turbine. This steam quickly brakes the speed of the turbine inahead direction, and then quickly accelerates it in astern direction. Asthe turbine attains a predetermined speed in astern direction, thepressure developed by the gear pump in the conduit 45 acts on the piston66 against the force of the spring 68 and shuts the valve 62.

The apparatus is now maintained in astern operation by the action ofhigh pressure steam on the reciprocating engine, and no power developedby the turbine.

It will be apparent, however, that the spring 68 (or the orifice 56) maybe so designed or the orifice 56 may be so adjusted that high-pressuresteam may be normally admitted to the astern section 21 during asternoperation, if this is desired.

Assume now, that it is desired again to reverse and resume aheadoperation. The throttle valve 9 is closed, the reversing mechanism 33again moved to ahead position, and the throttle valve 9 again opened.The valve 62 is held closed above described, but the valve 61 is openeddue to the absence of pressure in the conduit 44.

High-pressure steam is, therefore, admitted by the valve 61 to the aheadsection of the turbine, until the desired ahead speed is obtained, whenthe pressure in the conduit 44 moves the piston 63 to close the valve61.

Should the auxiliary source of fluid pressure transmitted through. theconduit '78 fail for any reason, the spring 84 would move the piston toclose the throttle valve 81, thereby shutting oiT all supply ofhigh-pressure steam to the turbine, which would otherwise be permitted,due to the action of the springs and 68.

It will be seen that in this embodiment, the high-pressure steam isautomatically admitted to the turbine to obtain a quick reversal of thedirection of operation, only a normal operation of the throttle valveand reversing mechanism of the reciprocating engine being necessary.

From the foregoing, it will be apparent that I have devised a marinepropulsion organization employing a reciprocating steam engine and aturbine arranged in compound relation with means for securing quick andpositive reversal of the organization, thereby overcoming a disadvantageheretofore present due to slow reversal.

What I claim is:

1. The combination with a reciprocating engine having a reversingmechanism, a turbine having ahead and astern sections, and means forsupplying steam exhausted from the reciprocating engine to the turbine,of means for supplying high-pressure steam to the ahead and asternsections and controlling means for the last-named means connected tosaid reversing mechanism, whereby, when the reversing mechanism isoperated to change the direction of the reciprocatingengine,high-pressure steam is admitted to one of the turbine sections to changethe direction of the turbine, said controlling means being operative toshut off the admission of high pressure steam to the turbine in responseto a pre-determined speed thereof.

2. The combination with a reciprocating engine having a reversingmechanism and a turbine having forward and reverse sections, of firstpassages for supplying steam exhausted from the reciprocatin engine tothe forward turbine section, second passages for supplying high-pressuresteam to the turbine sections, valves in said first and second passages,and means connected to the valves and to said reversing mechanism tosecure admission of high-pressure and exhaust steam to the ahead sectionor of high pressure steam to the astern section dependent upon theposition of the reversing mechanism and responsive to a pre-determinedspeed of the turbine for shutting oil admission of high pressure steamthereto.

3. In a marine propulsion power plant, the combination of areciprocating steam engine having a reversing mechanism, a turbinehaving ahead and astern sections, means for supplying exhaust steam fromthe reciprocating engine to the ahead section, means for supplyinghigh-pressure steam to said ahead and astern sections, and meansresponsive to operation of said reversing mechanism for interrupting thesupply of steam to one section and for rendering the high-pressure steamsupply means effective for supplying high-pressure steam to the othersection, and for interrupting the supply of high pressure steam to saidother section in response to a pre-determined speed.

4. In a marine propulsion power plant, the combination of areciprocating steam engine having a reversing mechanism, a turbinehaving ahead and astern sections, means for supplying exhaust steam fromthe reciprocating engine to the ahead section, means for supplyinghigh-pressure steam to the astern section, means responsive to operationof the reversing mechanism in changing the reciprocating engine fromahead to astern operation to interrupt the supply of exhaust steam tothe ahead section and tc render effective the means for supplyinghigh-pressure steam to the astern section, and means responsive to thespeed of the turbine for shutting off the supply of highpressure steam.

5. In a marine propulsion power plant, the combination of areciprocating steam engine having a reversing mechanism, a turbinehaving ahead and astern sections, means for supplying exhaust steam tothe ahead section, means for supplying high-pressure steam to the aheadand astern sections, means responsive to operation of the reversingmechanism in changing the engine from ahead operation to asternoperation for interrupting the supply of exhaust steam to the aheadsection and for rendering the high-pressure steam supply means effectivefor supplying high-pressure steam to the astern section and responsiveto operation of the reversing mechanism in changing the engine fromastern operation to ahead operation for rendering both of said steamsupply means effective to admit exhaust and high-pressure steam to theahead section, and means responsive to speed of the turbine for shuttingoff the supply of high-pressure steam.

6. The combination with a reciprocating engine having reversingmechanism and a turbine operated by exhaust steam received from thereciprocating engine, of means for supplying highpressure steam to theturbine, and means responsive to operation of the reversing mechanismfor rendering the high-pressure steam supply means effective and meansresponsive to the speed of the turbine for rendering the sameineffective.

WARREN B. FLANDERS.

